Charged Beads released, find maximum speed.

AI Thread Summary
Bead A, with a mass of 12.5 g and a charge of -7.74 nC, and Bead B, with a mass of 28.1 g and a charge of -10.7 nC, are released from a distance of 12.3 cm. The potential energy of the system is calculated as 6.06 x 10^-6 J, leading to questions about how to determine the maximum speed and acceleration of each bead. The discussion reveals confusion regarding the calculation of force as the beads approach each other, particularly concerning the nature of forces between like charges. It is clarified that the force between the beads is attractive, despite both being negatively charged, and that the maximum force occurs when they are first released. Understanding these concepts is essential for solving the problem accurately.
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Homework Statement



Bead A has a mass of 12.5 g and a charge of -7.74 nC. Bead B has a mass of 28.1 g and a charge of -10.7 nC. The beads are held 12.3 cm apart (measured between their centers) and released. What maximum speed is acheived by each bead? (Enter your answer for Bead A first.)

Homework Equations



U=Kq1q2/r

The Attempt at a Solution



I found the potential energy of the system as 6.06 x 10^-6 J but I don't know how to solve for the component of the potential that each bead would receive. Any ideas?

Thank you in advance.

EDIT: I figured it out. But now I need to use this same info to find maximum acceleration which is confusing me as it would be a non-constant acceleration that would peak when they were closest together. However, when calculating force between them I'm having trouble understanding how to calculate it as when the distance between the beads approaches zero, does the force not approach infinity?
 
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What's the direction of the force that's operating on each bead?
 
gneill said:
What's the direction of the force that's operating on each bead?

Towards the other bead. I got the correct answer by using the force they apply to each other when first released but I'm still confused as to why that's the maximum force. Would the force not get stronger the closer they get together?
 
So, you're saying that two negative charges will attract?
 
Oops, ok that explains it lol. Need to read that more carefully next time. Thanks!
 
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